SPL Model 2161 - Lundahl Microphone Input Transformer KitLundahl is the renowned Swedish manufacturer of excellent audio transformers, which can be optionally installed in appropriately prepared SPL devices. Sound Transformers can be used as an alternative to electronic balancing stages in the inputs and outputs. The bass and fundamental range becomes rounder, fuller and gets more pressure, the high and overtone range sounds a bit silkier and more present. Reasons are reduced portions of odd harmonics